Malcolm macleod



' Unites STATES PATENT Ursula.

ALcoLMMAc non, or MtNOHESTER, COUNTY or LANCASTER, ENGLAND,

ASSIGNOR or on E-HAEF TO EDWIN M. 'YELLAND, or PHILADELPHIA, PA.

Y ASPHALT PAVEMENT.

SPECIFICATION forming part of Letters Patent No. 355,023, dated December 28, 1886.

Application filed September 3, 1886. Serial No 212,625. (N o specimens.) Patented in England January 12, 1885, No. 406.

. declare the following to be a full, clear, and

exact description of the same.

The nature of my invention will fully appear from the following specification andclaims.

I am'enabled by my device to lay a bed of asphalt of a low melting mperature beneath abed or surface of higher melting temperature, theintermediate layer of limestone, granite, gravel, or other similar material prevent ing. the high temperature of the upper and harder asphalt'from melting, and so mixing itself with the lower or softer asphalt.

I have several methods of carrying out my invention, but prefer the following as the best: I prepare a sufiicient quantity of, say, British asphalt, composed of pitch and oil, in the V usual way. This varnish, when sufticiently prepared, I pour over broken limestone, (by

preference, but can use any-hard material.) I This I spread over the surface it is intended ing or ramming. Over this surface I spread ,a layer of limestone, granite, gravel, or other suitable material of about, say, an inch in diameter. This I ram into the rolled surface and pass over all a heavy roller until the limestone, granite, gravel, or other suitable material is forced into the foundation to about half its thickness, and the whole is i' ioroughly' compressed. I then remove any loose limestone or other material. Upon the foundation thus prepared I lay a bed or surface of rock or other hard asphalt prepared in the usual 'way. The layer of limestone or other material now prevents the fioating oils or other substances of the softer or lower asphalt from rising into the rock or other hard asphalt, and absorbs them partly into itself. The hot rock or other hard asphalt readily adheres to the limestone, granite, or other intermediate materm], and the whole forms a homogeneous mass, the intermediate layer of limestone or other suitable material acting as a key to connect the two asphalts.

In the case of roadways, where a safer hold for horses is desired, I lay the foundation 1n the way described for pavements, but prefer to put down the hard asphalt in two layers, viz: After the basic layer of limestone or other material is laid I cover it with a layer of hot rock asphalt, and upon it spread evenly pieces of stone or other similar material and cornpress them into the hard asphalt while it is hot, so that their upper surfaces are level with the completed height of the roadway. I then till in the spaces between the stones with hot rock or other hard asphalt and compress the whole firmly. A safer footing is thus pro vided for horses. The intermediate layer of limestone, granite, or other suitable material I prefer inmost cases to use dry, but can use it more or less impregnated to suit particular kinds of asphalt.

In order to cover my invention I shall in the claims use the words stony particles in a generic sense, to include all those well-known equivalents which will suggest themselves to theintelligent mind,such as slag, slate,stone,

gravel-stones, broken stone of all kinds, and,

generally, all hard refuse material.

What I claim as new is' 1. A pavement, roofing, or flooring composed of two layers of asphalt, said layers being of different melting temperatures, and united to one another without mixing by means of an intermediate keying of limestone,

granite, or other suitable material projecting from the lower through the upper layer of asphalt, substantially as described.

2. A composite pavement consisting of a lower layer of asphaltum or'ccment, a superincumbent layer of asphaltum or cement, and an intermediate layer of stony particles 'pro-' jccting into the lower layer or stratum and through the upper stratum of asphaltum or cement, substantially as and for the purposes described.

, MALCOLM MAGLEOD. Witnesses:

ARTHUR G. HALL, ALBERT E. HALL,

9 Maruz'h, Manchester, England.

DEPARTMENT OF THE INTERIOR,

UNITED STATES PATENT OFFICE,

Washington, D. 0., April 5, 1887'.

Whereas, The party in interest has declined to receive Letters Patent, No. 355,023, granted Decen her 28, 1886, upon the application of I Malcolm Macleod, of Manchester, County of Lancaster, England, for an improvement in Asphalt Pavements, for the reason that the name of Edwin M. Yelland was included therein as an assignee of onehalf the right, title, and interest in said invention, and

I Whereas, An examination of the files shows that said Letters Patent were not issued in accordance with the correct oficial record of the case.

It is hereby ordered, That the seal of said Letters Patent be broken, the grant returned to the file marked canceled and that Letters Patent in proper form he issued pursuant to the record of the case in the Patent Office.

' M. v. MONTGOMERY,

Commissioner of Patents.

Approved:

H. L. MULDROW,

Acting Secretary of the Interior. 

